Bearing member, end member, photosensitive drum unit, developing roller unit, process cartridge, intermediate member, and bearing member body

ABSTRACT

A bearing member is configured to be arranged in an end portion of a columnar rotary body, in which a shaft member is attached to the bearing member. The bearing member includes a body which includes a cylindrical body and a holding portion which is arranged inside the cylindrical body, and an intermediate member which is held by the holding portion of the body. The holding portion includes an intermediate member guide which guides the intermediate member so that the intermediate member rotates. The intermediate member includes a portion in which the shaft member is arranged.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/580,288, filed on Dec. 23, 2014, which is a continuation ofInternational Patent Application No. PCT/JP2014/068489, which was filedon Jul. 10, 2014 based on Japanese Patent Application No. 2013-146354,filed on Jul. 12, 2013, Japanese Patent Application No. 2014-090277,filed on Apr. 24, 2014, and Japanese Patent Application No. 2014-118089,filed on Jun. 6, 2014, the contents of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a process cartridge which is detachablyincluded in an image forming apparatus such as a laser printer and acopy machine, a photosensitive drum unit which is included in theprocess cartridge, a developing roller unit, an end member which isattached to a columnar rotary body of the photosensitive drum unit orthe developing roller unit, a bearing member which configures the endmember, an intermediate member which is included in the bearing member,and a bearing member body.

2. Description of the Related Art

An image forming apparatus such as a laser printer and a copy machineincludes a process cartridge which is provided to be attachable to anddetachable from an image forming apparatus body (hereinafter, referredto as an “apparatus body”).

The process cartridge is a member which forms contents which are to beshown, such as characters and figures, and which transfers thesecontents to a recording medium such as a paper sheet. More specifically,the process cartridge includes a photosensitive drum in which thecontents to be transferred are formed. In addition, other various unitsfor forming the contents which are to be transferred to thephotosensitive drum are arranged together in the process cartridge. Forexample, these units include a developing roller unit, a charging rollerunit, and a cleaning unit.

In a case of the process cartridge, the same process cartridge isattached to or detached from the apparatus body for maintenance purpose,or a new process cartridge is mounted on the apparatus body after theold process cartridge is detached from the apparatus body. Users of theimage forming apparatus can carry out such attachment and detachmentwork of the process cartridge by themselves. Therefore, from this pointof view, it is desirable that the attachment and detachment work becarried out as easily as possible.

However, a drive shaft of the apparatus body is configured so as toengage with the photosensitive drum included in the process cartridgedirectly or via other members. This causes the photosensitive drum toreceive a rotation force from the drive shaft and to rotate. Therefore,in order to attach and detach the process cartridge to and from theapparatus body, on each occasion, it is necessary to carry outdisengagement work (detachment) and re-engagement work (mounting)between the drive shaft of the apparatus body and the photosensitivedrum.

Therefore, if the photosensitive drum (process cartridge) can beattached to and detached from the drive shaft by moving thephotosensitive drum in a direction along an axis of the drive shaft ofthe apparatus body, it is possible to configure a relatively simpleapparatus. However, in a viewpoint of downsizing of the image formingapparatus and ensured space arrangement required for the attachment anddetachment work of the process cartridge, it is preferable that theprocess cartridge be detached from the apparatus body so as to be pulledout in a direction different from the direction along the axis of thedrive shaft, or so as to be pushed in an opposite direction when beingattached.

JP-A-2010-26473 discloses a configuration in which the process cartridgeis attached to and detached from the apparatus body in the directiondifferent from the direction along the axis of the drive shaft of theapparatus body. Specifically, a coupling member disclosed inJP-A-2010-26473 is attached to a drum flange (bearing member) so as tobe swingable by being provided with a spherical portion. Therefore, aportion (rotation force receiving member) which is included in thecoupling member and engages with the drive shaft of the apparatus bodyswings around the spherical portion, and can change an angle withrespect to the axis of the photosensitive drum. This facilitates theattachment and detachment between the drive shaft of the apparatus bodyand the photosensitive drum.

In addition, according to the invention disclosed in JP-A-2010-26473, ina structure for connecting a swinging shaft member to the bearingmember, a groove for introducing a rotation force transmission pinincluded in the shaft member to the bearing member is disposed on aninner peripheral side of the bearing member. This groove is formed so asto extend in a rotation direction. This groove facilitates theattachment of the rotation force transmission pin to the bearing member.

SUMMARY OF THE INVENTION

However, according to the inventions disclosed in JP-A-2010-26473 andTechnical Report Publication No. 2010-502200, Japan Institute ofInvention and Innovation, it is difficult to realize smooth attachmentof the shaft member to the bearing member, smooth swing of the shaftmember, and smooth attachment and detachment between the shaft memberand the apparatus body. For example, specifically, each member needs tohave high accuracy in order to fulfill a desired function. Consequently,uneven quality of the shaft member has a great influence on thefunction.

In addition, according to a structure of the coupling member and a drumflange (bearing member) holding the coupling member which is disclosedin JP-A-2010-26473, there is provided a structure in which the couplingmember is swingable and the spherical portion is directly held by thedrum flange. Accordingly, it is necessary to forcibly attach and detachthe coupling member when the spherical portion is attached to the drumflange (bearing member). Then, the forcible attachment and detachmentmay cause damage to the shaft member. In this regard, there is a problemof poor workability, and the shaft member is disadvantageously affectedwhen in reuse.

In contrast, according to a structure disclosed in Technical ReportPublication No. 2010-502200, Japan Institute of Invention andInnovation, when the shaft member is swung, a tilting angle thereof islimited. Consequently, in some cases, a sufficient swing angle cannot beobtained.

Therefore, the present invention is made in view of the above-describedproblems, and an object thereof is to provide a bearing member which cantransmit a rotation force equivalent to that in the related art, whichcan be attached to and detached from an apparatus body, which issmoothly operated, and which is less likely to receive an influence fromuneven quality of a shaft member. In addition, there are provided an endmember, a photosensitive drum unit, a developing roller unit, a processcartridge, an intermediate member, and a bearing member body.

An aspect of the present invention provides a bearing member configuredto be arranged in an end portion of a columnar rotary body, wherein ashaft member is attachable to the bearing member. The bearing memberincludes a body that includes a cylindrical body and a holding portionwhich is arranged inside the cylindrical body, and an intermediatemember that is held by the holding portion of the body. The holdingportion includes an intermediate member guide which guides theintermediate member so that the intermediate member rotates, and theintermediate member includes a portion in which the shaft member isarranged.

According to some aspects of the present invention, the swing in atleast one direction is performed by the rotation of the intermediatemember and the body. Therefore, a smooth pivotal movement (swing of theshaft member) is possible. In this case, the pivotal movement (swing ofthe shaft member) has no relationship with a form of the shaft member.Accordingly, even if the shaft member side has slightly unevendimensions, it is possible to ensure sufficiently smooth swing. Inaddition, the limitation of the tilting angle is relieved when the shaftmember swings. Therefore, it is possible to tilt the shaft member moregreatly.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual view of an image forming apparatus body 10 and aprocess cartridge 20.

FIG. 2 is a diagram schematically illustrating a structure of theprocess cartridge 20.

FIG. 3A is an external perspective view of a photosensitive drum unit 30for describing a first embodiment, and FIG. 3B is an externalperspective view of an end member 40.

FIG. 4 is an exploded perspective view of a bearing member 41.

FIG. 5A is a plan view of a body 45 of the bearing member 41, and FIG.5B is a perspective view of the body 45 of the bearing member 41.

FIG. 6 is a cross-sectional view of the body 45 of the bearing member41.

FIG. 7A is a perspective view of an intermediate member 60, FIG. 7B is afront view of the intermediate member 60, and FIG. 7C is across-sectional view of the intermediate member 60.

FIG. 8A is a cross-sectional view of a shaft member 70, and FIG. 8B isanother cross-sectional view of the shaft member 70.

FIG. 9 is an enlarged view of a coupling member 71.

FIG. 10A is a cross-sectional view of the end member 40, and FIG. 10B isanother cross-sectional view of the end member 40.

FIG. 11A is a view illustrating an example where the shaft member 70 hasa tilted posture on a cross section of the end member 40, and FIG. 11Bis a view illustrating an example where the shaft member 70 has a tiltedposture on another cross section of the end member 40.

FIG. 12A is a perspective view illustrating a drive shaft 11 of an imageforming apparatus body, and FIG. 12B is a view for describing a posturewhere the drive shaft 11 is connected to a coupling member 71.

FIG. 13A is a view for describing a scene where a process cartridge ismounted on an apparatus body, and FIG. 13B a view for describing anotherscene where the process cartridge is mounted on the apparatus body.

FIG. 14 is a perspective view of an end member 140 which describes asecond embodiment.

FIG. 15 is an exploded perspective view of a bearing member 141.

FIG. 16A is a plan view of a body 145 of the bearing member 141, andFIG. 16B is a perspective view of the body 145 of the bearing member141.

FIG. 17 is a cross-sectional view of the body 145 of the bearing member141.

FIG. 18A is another cross-sectional view of the body 145 of the bearingmember 141, and FIG. 18B is further another cross-sectional view of thebody 145 of the bearing member 141.

FIG. 19A is a perspective view of an intermediate member 160, FIG. 19Bis a front view of the intermediate member 160, and FIG. 19C is across-sectional view of the intermediate member 160.

FIG. 20 is a cross-sectional view of an end member 140.

FIG. 21A is another cross-sectional view of the end member 140, and FIG.21B is further another cross-sectional view of the end member 140.

FIG. 22 is a view illustrating an example where the shaft member 70 hasa tilted posture on a cross section of the end member 140.

FIG. 23A is a view illustrating an example where the shaft member 70 hasa tilted posture on another cross section of the end member 140, andFIG. 23B is a view illustrating an example where the shaft member 70 hasa tilted posture on further another cross section of the end member 140.

FIG. 24A is a perspective view of an intermediate member 260, FIG. 24Bis a front view of the intermediate member 260, and FIG. 24C is a planview of the intermediate member 260.

FIG. 25A is a perspective view of a posture where the shaft member 70 isattached to the intermediate member 260, and FIG. 25B is across-sectional view of the posture where the shaft member 70 isattached to the intermediate member 260.

FIG. 26A is a plan view of a body 345 of a bearing member 341, and FIG.26B is a perspective view of the body 345 of the bearing member 341.

FIG. 27 is a cross-sectional view of the body 345 of the bearing member341.

FIG. 28A is another cross-sectional view of the body 345 of the bearingmember 341, and FIG. 28B is further another cross-sectional view of thebody 345 of the bearing member 341.

FIG. 29 is a perspective view of the bearing member 341.

FIG. 30A is a cross-sectional view of the bearing member 341, and FIG.30B is another cross-sectional view of the bearing member 341.

FIG. 31 is a view for describing a scene where the intermediate member160 is attached to the body 345.

FIG. 32 is a view for describing tilting of the shaft member 70 and aposition of a guide member 165.

FIG. 33A is a perspective view of a bearing member 341′, and FIG. 33B isa perspective view illustrating an enlarged portion of the bearingmember 341′.

FIG. 34 is a perspective view of the bearing member 341″.

FIG. 35A is a cross-sectional view of a body 445, and FIG. 35B isanother cross-sectional view of the body 445.

FIG. 36A is a perspective view of an intermediate member 460, FIG. 36Bis a front view of the intermediate member 460, and FIG. 36C is a planview of the intermediate member 460.

FIG. 37A is a view for describing a scene where the intermediate member460 is attached to the body 445, and FIG. 37B is a view for describing ascene where the intermediate member 460 swings inside the body 445.

FIG. 38 is a view for describing a form where the end member 40 isincluded in a developing roller unit 523.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, the present invention will be described with reference toembodiments illustrated in the drawings. However, the present inventionis not limited to the embodiments. In addition, for ease of description,each drawing illustrates members by omitting or seeing through somemembers if necessary, or by using an exaggerated shape. In some cases,hatching is given on a surface serving as an end surface incross-sectional views.

FIG. 1 is a diagram for describing a first embodiment, and is aperspective view schematically illustrating a process cartridge 20 whichincludes an end member 40 (refer to FIG. 2), and an image formingapparatus body 10 which is used by mounting the process cartridge 20thereon (hereinafter, referred to as an “apparatus body 10”). Asillustrated in FIG. 1, the process cartridge 20 can be mounted on theapparatus body 10 by being moved in a direction illustrated by arrow Ain FIG. 1, and can be detached from the apparatus body 10. The directionof (A) is a direction different from an axial direction of a drive shaftof the apparatus body 10. The apparatus body 10 and the processcartridge 20 configure an image forming apparatus. Hereinafter, detaileddescription will follow.

FIG. 2 schematically illustrates a structure of the process cartridge20. As is understood from FIG. 2, the process cartridge 20 is configuredso that an inner side of a housing 21 internally accommodates aphotosensitive drum unit 30 (refer to FIG. 3A), a charging roller unit22, a developing roller unit 23, a regulating member 24, and a cleaningblade 25. In a posture where the process cartridge 20 is mounted on theapparatus body 10, a recording medium such as a paper sheet is movedalong a line illustrated by II in FIG. 2. In this manner, an image istransferred onto the recording medium from the photosensitive drum unit30.

In addition, attachment and detachment of the process cartridge 20 toand from the apparatus body 10 are performed roughly as follows. In thepresent embodiment, the photosensitive drum unit 30 included in theprocess cartridge 20 is rotated by receiving a rotation driving forcefrom the apparatus body 10. Therefore, at least when operated, a driveshaft 11 (refer to FIG. 12A) of the apparatus body 10 and an end member40 (refer to FIG. 3B) of the photosensitive drum unit 30 engage witheach other. In this manner, the photosensitive drum unit 30 is in astate where the rotation force can be transmitted (refer to FIG. 12B).

In contrast, when the process cartridge 20 is attached to or detachedfrom the apparatus body 10, the drive shaft 11 and the end member 40need to quickly engage with each other or disengage from each other soas not to inhibit mutual movement to the other side or mutual rotationregardless of their postures.

In this manner, the end member 40 of the photosensitive drum unit 30properly engages with the drive shaft 11 of the apparatus body 10,thereby transmitting the rotation driving force.

Hereinafter, each configuration will be described.

As is understood from FIG. 2, the process cartridge 20 includes thecharging roller unit 22, the developing roller unit 23, the regulatingmember 24, the cleaning blade 25, and the photosensitive drum unit 30.These elements are internally accommodated inside the housing 21. Therespective elements are configured as follows.

The charging roller unit 22 charges a photosensitive drum 35 (refer toFIG. 3A) of the photosensitive drum unit 30 by using a voltage appliedfrom the apparatus body 10. The charging roller unit 22 is rotated tofollow the photosensitive drum 35, and comes into contact with an outerperipheral surface of the photosensitive drum 35, thereby performingthis charging.

The developing roller unit 23 is a member including a roller forsupplying a developer to the photosensitive drum 35. Then, anelectrostatic latent image formed in the photosensitive drum 35 isdeveloped by the developing roller unit 23. A fixed magnet is embeddedin the developing roller unit 23.

The regulating member 24 is a member which adjusts an amount of thedeveloper adhering to an outer peripheral surface of the developingroller unit 23 and applies a frictional electrostatic charge to thedeveloper itself.

The cleaning blade 25 is a blade which removes the developer remainingafter the transfer by coming into contact with the outer peripheralsurface of the photosensitive drum 35 and by using a distal end thereof.

The photosensitive drum unit 30 is a member whose surface has charactersor figures which are to be transferred to a recording medium such as apaper sheet. FIG. 3A illustrates an external perspective view of thephotosensitive drum unit 30. As is understood from FIG. 3A, thephotosensitive drum unit 30 includes the photosensitive drum 35, a lidmember 36, and the end member 40. FIG. 3B illustrates a perspective viewfocusing on the end member 40. Hereinafter, the photosensitive drum unit30 will be described with reference to FIGS. 2A and 2B and appropriatedrawings.

The photosensitive drum 35 is a member in which an outer peripheralsurface of a drum cylinder (sometimes referred to as a “substrate”)serving as a columnar rotary body is coated with a photosensitive layer.That is, the drum cylinder is a conductive cylinder made of aluminum,and is configured so that the cylinder is coated with the photosensitivelayer. As will be described later, the end member 40 is attached to oneend of the photosensitive drum 35, and the lid member 36 is arranged inthe other end. In the present embodiment, the drum cylinder isconfigured to have a cylindrical hollow shape, but may be configured tohave a solid round bar shape. However, at least the lid member 36 andthe end member 40 are formed so as to be properly attached to an endportion thereof.

The lid member 36 is a member formed of a resin, in which a fittingportion fitted to an inside of a cylinder of the photosensitive drum 35and a bearing portion arranged to cover one end surface of thephotosensitive drum 35 are formed coaxially. The bearing portion has adisk shape covering the end surface of the photosensitive drum 35, andincludes a portion for receiving a shaft disposed inside the processcartridge. In addition, a ground plate formed of a conductive materialis arranged in the lid member 36, thereby electrically connecting thephotosensitive drum 35 and the apparatus body 10 to each other.

Without being limited to this lid member described as an example of thepresent embodiment, other types of lid members which are generallyavailable can also be adopted. For example, a gear for transmitting therotation force may be arranged in the lid member. In addition, theabove-described conductive material may be disposed on the end member 40side (to be described later).

The end member 40 is a member attached to an end portion opposite to theabove-described lid member 36 within an end portion of thephotosensitive drum 35, and includes a bearing member 41 and a shaftmember 70.

The bearing member 41 is a member which is fixed to the end portion ofthe photosensitive drum 35. FIG. 4 illustrates an exploded perspectiveview of the bearing member 41. As is understood from FIG. 4, the bearingmember 41 includes a body 45 and an intermediate member 60. Each ofthese will be described.

FIG. 5A illustrates a view when the body 45 is viewed from a side towhich the intermediate member 60 is inserted, and FIG. 5B illustrates aview when the body 45 is viewed from a different angle from that in FIG.3B, respectively. In addition, FIG. 6 illustrates a cross-sectional viewtaken in an axial direction along a line illustrated by VI-VI in FIGS.4, 5A, and 5B. In the body 45 according to the present embodiment, across section in the axial direction along a line (line illustrated byVI′-VI′ in FIG. 5A) in which the line illustrated by VI-VI is rotated by90° around the axis of the body 45 is the same as that in FIG. 6.

In the present embodiment, the body 45 includes a cylindrical body 46having a cylindrical shape as is understood in FIGS. 3 to 6. Inaddition, an outer peripheral surface of the cylindrical body 46 has aring-shaped contact wall 47 erected along the outer peripheral surface,and a gear 48. An outer diameter of the cylindrical body 46 issubstantially the same as an inner diameter of the above-describedphotosensitive drum 35. One end side of the cylindrical body 46 isinserted into and fitted to the photosensitive drum 35, thereby fixingthe body 45 to the photosensitive drum 35. In this case, the cylindricalbody 46 is inserted to a depth which allows the end surface of thephotosensitive drum 35 to come into contact with the contact wall 47. Inthis case, an adhesive may be used for more strengthened fixing. Inaddition, a groove 46 a or concave and convex portions may be disposedin the cylindrical body 46 of a portion in which the adhesive isarranged. This causes the adhesive to be held in the groove 46 a or theconcave portion, thereby further strengthening adhesion between thephotosensitive drum 35 and the body 45.

The gear 48 is a gear for transmitting the rotation force to thedeveloping roller unit 23, and is a helical gear in the presentembodiment. Without being particularly limited thereto, a type of thegear may be a spur gear. However, the gear may not be necessarilydisposed.

A plate-shaped bottom portion 49 is disposed on a cylindrical inner sideof the cylindrical body 46 so as to close at least a portion of theinner side of the cylindrical body 46. Furthermore, within the innerside of the cylindrical body 46 which is partitioned by the bottomportion 49, a holding portion 50 is disposed on an inner side oppositeto a side which is fixed to the photosensitive drum 35.

Here, an example including the bottom portion 49 has been described, butthe bottom portion 49 may not be necessarily disposed. As will bedescribed later, the shaft member 70 and the intermediate member 60 canbe held by the holding portion 50. Accordingly, without disposing thebottom portion 49, it is possible to hold the shaft member 70 and theintermediate member 60 inside the cylindrical body 46.

The holding portion 50 forms guide grooves 51, 52, 53, and 54 whichserve as an intermediate member guide, inside the cylindrical body 46.Therefore, in the holding portion 50, multiple projections 50 a arearranged at predetermined gaps along an inner peripheral surface of thecylindrical body 46 so as to project from an inner surface of thecylindrical body 46 toward the axis of the cylindrical body 46. The gapsbetween the adjacent projections 50 a form the guide grooves 51, 52, 53,and 54. In addition, a space (concave portion) is formed in the axisportion surrounded by the projections 50 a, and a proximal end portion(spherical body 90, refer to FIGS. 8A and 8B) of the shaft member 70 isarranged therein as described herein.

Here, in the guide grooves, two guide grooves opposing each other acrossthe axis of the cylindrical body 46 function as a pair. Then, the guidegroove may actually be used as one pair as will be described later.However, as in the present embodiment, four guide grooves 51, 52, 53,and 54, that is, two pairs may be disposed. Furthermore, six (threepairs) or more guide grooves may be disposed. This can improve thebalance of material behavior (sink mark) when the body 45 isinjection-molded, and can manufacture a more accurate body. Therefore,the number of guide grooves may be determined in terms of the materialbehavior.

Herein, a pair of guide grooves configured to have the guide grooves 51and 52 whose cross-sections are illustrated in FIG. 6 will be described.Another pair of guide grooves configured to have the guide grooves 53and 54 is the same as the above-described pair, and thus, descriptionthereof will be omitted.

As described above, the guide groove 51 is a groove which extends alonga direction of the axis (illustrated by line O in FIG. 6) of thecylindrical body 46 formed on an inner peripheral surface of thecylindrical body 46. Then, the guide groove 51 is configured so that theaxis O side of the cylindrical body 46 is open, and has a bottom surfaceon an inner peripheral surface side of the cylindrical body 46. Incontrast, the guide groove 52 is a groove disposed so as to oppose theguide groove 51 on the opposite side across the axis O of thecylindrical body 46. Similar to the guide groove 51, the guide groove 52is formed on the inner peripheral surface of the cylindrical body 46,and extends along the direction of the axis O of the cylindrical body46. Then, the guide groove 52 is also configured so that the axis O sideof the cylindrical body 46 is open, and has a bottom surface on an innerperipheral surface side of the cylindrical body 46.

In addition, as is understood from FIG. 6, at least a portion of thebottom surfaces of the guide grooves 51 and 52 have curved surfaces 51 aand 52 a which are curved with respect to a direction along the axis Oof the cylindrical body 46. It is preferable that the curved surfaces 51a and 52 a be configured as follows in a cross section illustrated inFIG. 6.

The curved surfaces 51 a and 52 a are disposed to oppose each other soas to be line-symmetrical across the axis O of the cylindrical body 46,and a gap between the curved surfaces 51 a and 52 a is narrowed as thecurved surfaces 51 a and 52 a are away from the bottom portion 49 side(side inserted into the photosensitive drum 35). In this manner, it ispreferable to form the curved surfaces to be close to each other. Aswill be described later, this can hold the intermediate member 60 so asnot to be detached from the body 45.

It is preferable that the curved surfaces 51 a and 52 a have an arcshape and belong to the same circle, and that the center of the circlebe located on the axis O. This can hold the intermediate member 60 inthe body 45 in the direction along the axis O without looseness.Accordingly, it is possible to swing (tilt) the shaft member 70 bysmoothly guiding the rotation of the intermediate member 60.

In addition, when the bottom portion 49 is provided, the bottom portion49 may be arranged on the circumference of the circle to which thecurved surfaces 51 a and 52 a belong so that an intersection point(point illustrated by B in FIG. 6) with a surface on the curved surfaces51 a and 52 a side is present between the axis O and the bottom portion49 of the cylindrical body 46.

A material configuring the body 45 is not particularly limited, but itis possible to use a resin such as polyacetal, polycarbonate, or PPS.Here, in order to improve rigidity of the member, glass fibers or carbonfibers may be mixed with the resin, depending on load torques. Inaddition, in order to obtain a smooth swing operation when theintermediate member 60 is attached to the body 45, sliding performancemay be improved by causing the resin to contain at least one type amongfluorine, polyethylene, and silicone rubber. In addition, the resin maybe coated with fluorine, or lubricant may be applied to the resin.

Referring back to FIG. 4, the intermediate member 60 will be described.As is understood from FIG. 4, the intermediate member 60 is an annularmember which is partially cut out. FIGS. 7A and 7B illustrate theintermediate member 60. FIG. 7A is a perspective view, FIG. 7B is afront view, and FIG. 7C is a cross-sectional view taken along a lineillustrated by VIIc-VIIc in FIG. 7B.

The intermediate member 60 has an annular shape in which a cutoutportion 60 a is partially disposed.

In the intermediate member 60, a portion on an outer periphery thereoffunctions as a guided portion by being inserted into the inner side of apair of grooves among the guide grooves 51, 52, 53, and 54 which areincluded in the holding portion 50 of the above-described body 45.Therefore, the outer diameter of the intermediate member 60 has a sizewhich enables the intermediate member 60 to slide therein by beingaccommodated inside the pair of guide grooves in which the outerperipheral portion of the intermediate member 60 is arranged. When atleast a portion of the bottom surface of the guide grooves 51, 52, 53,and 54 has an arc shape as described above, and when the arc belongs tothe same circle in the pair of opposing guide grooves, it is preferablethat the diameter of the circle be the same as the outer diameter of theintermediate member 60. This enables the intermediate member 60 to besmoothly and rotated between the guide grooves, and can suppress thelooseness.

In contrast, the proximal end portion of the shaft member 70 (to bedescribed later) is arranged on an annular inner side of theintermediate member 60. Accordingly, the annular inner side may have asize and a form which can accommodate at least a portion of the proximalend portion inside the intermediate member 60. In the presentembodiment, the proximal end portion of the shaft member 70 is aspherical body 90 (refer to FIGS. 8A and 8B). Accordingly, the innerdiameter of the intermediate member 60 can be configured to be the sameas the diameter of the spherical body 90. In addition, as is understoodfrom FIG. 7C, the inner peripheral surface of the intermediate member 60is also curved in an arc shape in a direction along the axis of the ring(vertical direction on a paper surface in FIG. 7C). The curve can matchthe curve on the outer periphery of the spherical body 90. This enablesthe intermediate member 60 and the spherical body 90 to be more suitablycombined with each other.

Then, the size (that is, thickness) in the direction along the axis ofthe ring of the intermediate member 60 is substantially the same as thewidth of the guide grooves 51 and 52 which are formed in the holdingportion 50 of the above-described body 45.

The cutout portion 60 a of the intermediate member 60 has a size and ashape in which at least a portion of a rotary shaft 85 (refer to FIGS.8A and 8B) of at least the shaft member 70 (to be described later) canbe arranged thereinside. Therefore, an end surface 60 b of theintermediate member 60 in which the cutout portion 60 a is formed canalso match the shape of the rotary shaft 85. In the present embodiment,an enlarged diameter portion 85 a is disposed in the rotary shaft 85,and a tapered portion is disposed herein (refer to FIGS. 8A and 8B).Accordingly, the end surface 60 b of the intermediate member 60 isformed so as to have a valley in a V-shape which can receive the taperedportion.

Two grooves 61 and 62 extending outward from an inner peripheral surfaceof the ring are disposed in the intermediate member 60. The two grooves61 and 62 are disposed at positions opposing each other along a diameterof the intermediate member 60. Both ends of a rotation forcetransmission pin 95 (refer to FIGS. 8A and 8B) of the shaft member 70(to be described later) are respectively inserted into the grooves 61and 62. Therefore, a shape and arrangement of the grooves 61 and 62 areconfigured so that the end portions of the rotation force transmissionpin 95 can be respectively inserted into the grooves 61 and 62.

In addition, it is preferable that pieces 61 a and 62 a remain in one ofthe grooves 61 and 62 in the axis direction of the ring of theintermediate member 60, and that the grooves 61 and 62 do not penetratein the direction along the axis. In this manner, when the shaft member70 is assembled to the intermediate member 60 and the rotation force isapplied to the shaft member 70 from the apparatus body 10, the rotationforce transmission pin 95 is caught on by the pieces 61 a and 62 a sothat the rotation fore can be properly transmitted to the intermediatemember 60. Therefore, in view of the rotation of the rotation forcetransmission pin 95, as is well understood from FIGS. 7A to 7C, thepiece 61 a of the groove 61 and the piece 62 a of the groove 62 aredisposed on different sides in the axial direction of the intermediatemember 60.

If a distal end of the rotation force transmission pin 95 extends toreach the inside of the guide grooves 51 and 52 of the holding portion50 of the body 45, the distal end of the rotation force transmission pin95 is caught on by a lateral wall of the guide grooves 51 and 52 whenrotated. Accordingly, since the rotation force can be transmitted, thepieces 61 a and 62 a may not be necessarily disposed.

In addition, an opening portion opposing the pieces 61 a and 62 a withinthe grooves 61 and 62 may be slightly narrowed as compared to the insideof the groove. Specifically, the opening portion can be configured tohave an opening which is slightly smaller than a diameter of therotation force transmission pin 95. In this manner, the rotation forcetransmission pin 95 which has entered the inside of the grooves 61 and62 once is less likely to slip out from the grooves 61 and 62 by thenarrowed opening portion.

A material configuring the intermediate member 60 is not particularlylimited, but it is possible to use a resin such as polyacetal,polycarbonate, and PPS. Here, in order to improve rigidity of themember, glass fibers or carbon fibers may be mixed with the resin,depending on load torques. In addition, in order to obtain a smoothswing operation when the intermediate member 60 is attached to the body45, sliding performance may be improved by causing the resin to containat least one type among fluorine, polyethylene, and silicone rubber. Inaddition, the resin may be coated with fluorine, or lubricant may beapplied to the resin.

Referring back to FIGS. 3A and 3B, the shaft member 70 within the endmember 40 will be described. FIG. 8A illustrates a cross-sectional viewtaken along VIIIa-VIIIa of the shaft member 70 illustrated in FIG. 3B,and FIG. 8B illustrates a cross-sectional view taken along VIIIb-VIIIbof the shaft member 70 illustrated in FIG. 3B, respectively. Two crosssections are shifted by 90° around the axis. As is understood from FIGS.3B, 8A, and 8B, the shaft member 70 includes a coupling member 71, therotary shaft 85, the spherical body 90, and the rotation forcetransmission pin 95.

The coupling member 71 is a portion which functions as a rotation forcereceiving portion for receiving the rotation driving force from theapparatus body 10 (refer to FIG. 1). FIG. 9 illustrates an enlarged viewof the coupling member 71. As is understood from FIGS. 3B, 8A, 8B, and9, the coupling member 71 is a circular dish-shaped member, and aninside thereof has a bottom portion 73 in which a conical concaveportion 73 a is disposed so that a portion through which the axis passesis the deepest.

In addition, a cylindrical engagement wall 74 is erected along an edgeof a surface on one surface side (opposite side to the side having therotary shaft 85) within surfaces of the bottom portion 73. Two pairs ofgrooves 74 a and 74 b which oppose each other across the axis of theshaft member 70 are disposed on the engagement wall 74. One pair of thegrooves 74 a and the other pair of the grooves 74 b are shifted by 90°around the axis.

As clearly illustrated in FIG. 9, a convex portion 75 is disposed on onelateral wall of the groove in the respective grooves 74 a and 74 b, andthe bottom portion 73 side thereof is provided with a recess 75 a in thecircumferential direction. In this manner, as will be described later, apin 11 b of the drive shaft 11 of the apparatus body 10 engages with therecess 75 a. Accordingly, the pin 11 b is prevented from slipping out,and the rotation force is properly transmitted (refer to FIG. 12B).

In addition, a tilted surface 74 c is formed on the other side lateralwall of the respective grooves 74 a and 74 b, thereby facilitatingintroduction of the above-described pin 11 b into the groove.

Therefore, a width of the groove 74 a illustrated by C in FIG. 9 isslightly larger than a diameter of the pin 11 b (refer to FIG. 12B), andis narrower than a diameter of a shaft portion 11 a so that the shaftportion 11 a of the drive shaft 11 cannot pass therethrough. An innerside diameter of the engagement wall 74 which is illustrated by D inFIG. 9 is formed to be slightly larger than the diameter of the shaftportion 11 a of the drive shaft 11, but is approximately the same. Howthe rotation force can be received from the drive shaft 11 will bedescribed later.

The present embodiment employs four (two pairs) grooves on theengagement wall, but the number is not particularly limited thereto. Two(one pair), six (three pairs) or more grooves may be employed. Inaddition, a form of the coupling member 71 has been specificallydescribed as an example, but the present embodiment is not necessarilylimited to the form. Any shape may be employed as long as the driveshaft 11 of the apparatus body 10 can engage with and disengage from thecoupling member 71.

The rotary shaft 85 is a columnar shaft-shaped member which functions asa rotation force transmission portion for transmitting the rotationforce received by the coupling member 71. Therefore, the above-describedcoupling member 71 is disposed in one end of the rotary shaft 85. Inaddition, in the present embodiment, the rotary shaft 85 is configuredto have the enlarged diameter portion 85 a in which the diameter of therotary shaft is partially enlarged. The enlarged diameter portion 85 aand the other portion are continuous with each other on a surface tiltedin a tapered shape.

The spherical body 90 functions as a proximal end portion, and is aspherical member in the present embodiment, as is understood from FIGS.8A and 8B. The spherical body 90 is included in an end portion oppositeto the side having the coupling member 71 within end portions of therotary shaft 85. In this case, it is preferable to cause the axis of therotary shaft 85 and the center of the spherical body 90 to coincide witheach other as much as possible. This enables the photosensitive drum 35to be more stably rotated. In addition, the diameter of the sphericalbody 90 is configured to have a size to be accommodated inside the ringof the intermediate member 60 of the above-described bearing member 41.It is preferable to configure the diameter so as to be approximately thesame as the inner diameter of the ring.

In the present embodiment, a case has been described in which theproximal end portion has a spherical shape, but the present embodimentis not limited thereto. For example, the present embodiment is notparticularly limited as long as the proximal end portion has a formwhich does not interfere with the swing of the shaft member, such as apartially spherical shape and an oval shape in which curved surfaces arecombinedly formed.

The rotation force transmission pin 95 is a columnar shaft-shaped memberwhich forms a rotation force transmission projection which projects fromthe proximal end portion by passing through the center of the sphericalbody 90, and by both ends protruding from the spherical body 90 afterpenetrating the spherical body 90. The axis of the rotation forcetransmission pin 95 is disposed so as to be orthogonal to the axis ofthe above-described rotary shaft 85.

A material configuring the shaft member 70 is not particularly limited,but it is possible to use a resin such as polyacetal, polycarbonate, andPPS. However, in order to improve rigidity of the member, glass fibersor carbon fibers may be mixed with the resin, depending on load torques.In addition, the rigidity may be further strengthened by inserting metalinto the resin, or the shaft member 70 may be entirely or partiallymanufactured by using the metal.

The bearing member 41 and the shaft member 70 are combined as follows soas to configure the end member 40. Description of this combination willfurther facilitate understanding of a shape, a size, and a positionalrelationship which are provided for the bearing member 41 and the shaftmember 70. FIG. 10A illustrates a cross-sectional view of the end member40 taken along line VIIIa-VIIIa illustrated in FIG. 3B, and FIG. 10Billustrates a cross-sectional view taken along line VIIIb-VIIIbillustrated in FIG. 3B, respectively. In addition, FIG. 11A illustratesan example of a tilting posture of the shaft member 70 in a viewpointillustrated in FIG. 10A, and FIG. 11B illustrates an example of atilting posture of the shaft member 70 in a viewpoint illustrated inFIG. 10B, respectively.

As is particularly well understood from FIG. 10B, the spherical body 90is arranged inside the ring of the intermediate member 60, and therotation force transmission pin 95 is inserted into the grooves 61 and62 of the intermediate member 60. This causes the intermediate member 60and the shaft member 70 to be combined with each other. Therefore, asillustrated by arrow XIa in FIG. 11A, the shaft member 70 can swingaround the axis of the rotation force transmission pin 95 with respectto the intermediate member 60.

In contrast, as is well understood from FIGS. 10A and 10B, in theintermediate member 60 in which the shaft member 70 is arranged, theouter peripheral portion of the intermediate member 60 is fitted intothe guide grooves 51 and 52 so that the thickness direction of theintermediate member 60 is the width direction of the guide grooves 51and 52 formed in the holding portion 50 of the body 45. Therefore, theouter peripheral portion of the intermediate member 60 is arrangedinside the guide grooves 51 and 52, and the intermediate member 60 canslidably move inside the guide grooves 51 and 52. As a result, theintermediate member 60 can be rotated inside the body 45 as illustratedby arrow XIb in FIG. 11B.

As in the present embodiment, if the curved surfaces 51 a and 52 aformed on the bottom surface of the guide grooves 51 and 52 are locatedon a circle and the outer periphery of the intermediate member 60 isformed to have substantially the same diameter as that of the circle,the intermediate member 60 is accommodated in the body without loosenessas illustrated in FIG. 10B. Accordingly, the end member 40 is allowed tomore excellently and accurately transmit the rotation.

As described above, in the end member 40 of the present embodiment, theintermediate member 60 is held by the guide grooves 51 and 52 formed inthe body 45 so as not to slip out, and the shaft member 70 is held bythe intermediate member 60 so as not to slip out. Therefore, the shaftmember 70 is not directly held by the body 45.

In addition, this assembly work of the end member 40 can be carried outby first arranging the shaft member 70 in the intermediate member 60 andattaching the intermediate member 60 to the body 45. In this case, whenthe intermediate member 60 is arranged inside the guide grooves 51 and52 of the holding portion 50, the assembly work can be carried outthrough elastic deformation using a weak force. Therefore, it ispossible to assemble the shaft member 70 to the bearing member 41 easilyand with increased productivity. In addition, not only the assembly workis facilitated, but also the detachment work is similarly facilitated.Accordingly, the reuse is also facilitated. Particularly, in this case,it is not necessary to deform the shaft member 70 during the insertionand the detachment. Accordingly, there is no more possibility of damage.In addition, since the detachment is facilitated, workability can alsobe improved.

As described above, the shaft member 70 is arranged inside the bearingmember 41, thereby enabling the shaft member 70 to swing as illustratedin FIGS. 11A and 11B. That is, in a viewpoint illustrated in FIG. 11A,the shaft member 70 can swing around the axis of the rotation forcetransmission pin 95 as illustrated by arrow XIa. In contrast, in aviewpoint illustrated in FIG. 11B, the shaft member 70 can swing tofollow the rotation of the intermediate member 60 as illustrated byarrow XIb. The swing illustrated in FIG. 10A and the swing illustratedin FIG. 11B are swings in a direction in which the swings are orthogonalto each other.

In addition, when the driving force is received from the apparatus body10, the shaft member 70 receives the rotation force acting around theaxis as illustrated by arrow X in FIGS. 10A and 10B. In this case, bothend portions of the rotation force transmission pin 95 of the shaftmember 70 press the intermediate member 60, and the intermediate member60 is caught on by the lateral wall of the guide grooves 51 and 52 ofthe body 45. In this manner, the rotation force can be transmitted tothe photosensitive drum 35. When the distal end of the rotation forcetransmission pin 95 is configured to reach the inside of the guidegrooves 51 and 52, even if the pieces 61 a and 62 a (refer to FIG. 7C)are not provided, the distal end of the rotation force transmission pin95 is caught on by the lateral wall of the guide grooves 51 and 52 ofthe body 45. In this manner, the rotation force can be transmitted tothe photosensitive drum 35.

As described above, according to the end member 40, the swing of theshaft member 70 in at least one direction enables the intermediatemember 60 and the body 45 to slide and swing, thereby allowing a smoothoperation. In this case, the swing has no relationship with a form ofthe shaft member. Accordingly, even if the shaft member side hasslightly uneven dimensions, it is possible to ensure sufficiently smoothswing. In addition, even if an angle of the swing increases, there is nopossibility that the shaft member 70 slips out therefrom. Therefore, itis possible to increase the angle of the swing. This can minimize a gapbetween the photosensitive drum (process cartridge) and the drive shafton the apparatus body side. Accordingly, it is possible to miniaturizethe apparatus body.

In addition, according to the end member 40, it is not necessary todispose the groove (introduction groove) for introducing the rotationforce transmission pin into the swing groove as disclosed in Non PatentLiterature 1. It is possible to solve the problem that the shaft memberaccidentally slips out during the operation.

The above-described configuration enables the shaft member 70 to bepivotally moved (swing), to transmit the rotation force, and to be heldby the bearing member 41.

The end member 40 is attached to the photosensitive drum 35 by insertingthe end portion on a side where the shaft member 70 does not protrudewithin the end member 40 into the photosensitive drum 35 after the endmember 40 is assembled as illustrated in FIGS. 10A and 10B. This endmember 40 properly applies the rotation force to the photosensitive drum35 when the process cartridge 20 is mounted on the apparatus body 10,and enables the process cartridge 20 to be easily attached and detached.

As described above, the photosensitive drum unit 30, the charging rollerunit 22, the developing roller unit 23, the regulating member 24, andthe cleaning blade 25 are rotatably accommodated inside the housing 21of the process cartridge 20 (refer to FIG. 2). That is, each memberfulfills its function by being rotated inside the housing whennecessary.

Then, in the present embodiment, at least the coupling member 71 withinthe shaft member 70 of the photosensitive drum unit 30 is arranged to beexposed from the housing 21. As will be described later, this enablesthe rotation driving force to be obtained from the apparatus body 10,and facilitates the attachment and detachment between the apparatus body10 and the process cartridge 20.

Here, each member included in the process cartridge 20 has beendescribed as an example, but a member included herein is not limitedthereto. It is preferable to provide a member, a portion, and adeveloper which are normally included in other process cartridges.

Next, the apparatus body 10 will be described. The apparatus body 10according to the present embodiment is a laser printer. The laserprinter is operated in a posture where the above-described processcartridge 20 is mounted thereon. When forming an image, thephotosensitive drum 35 is rotated, and the charging roller unit is usedin charging. In this state, the laser printer uses various opticalmembers included herein, emits laser beams corresponding to imageinformation to the photosensitive drum 35, and can obtain anelectrostatic latent image based on the image information. The latentimage is developed by the developing roller unit 23.

In contrast, a recording medium such as a paper sheet is set on theapparatus body 10, and is transported to a transfer position by afeeding roller and a transport roller which are disposed in theapparatus body 10. A transfer roller 10 a (refer to FIG. 2) is arrangedat the transfer position, and a voltage is applied to the transferroller 10 a whenever the recording medium passes therethrough. In thismanner, the image is transferred to the recording medium from thephotosensitive drum 35. Thereafter, heat and pressure are applied to therecording medium, thereby fixing the image onto the recording medium.Then, the recording medium on which the image is formed is dischargedfrom the apparatus body 10 by a discharge roller.

As described above, in a posture where the process cartridge 20 ismounted thereon, the apparatus body 10 applies the rotation drivingforce to the photosensitive drum unit 30. Therefore, how the rotationdriving force is applied from the apparatus body 10 to thephotosensitive drum unit 30 in the posture where the process cartridge20 is mounted thereon will be described.

The rotation driving force is applied to the process cartridge 20 by thedrive shaft 11 serving as a rotation force applying portion of theapparatus body 10. FIG. 12A illustrates a shape of a distal end portionof the drive shaft 11. As is understood from FIG. 12A, the drive shaft11 has a shaft portion 11 a which is a columnar shaft member whosedistal end has a spherical surface, and a columnar pin 11 b serving as arotation force applying portion which protrudes in a directionorthogonal to the rotation axis illustrated by a dashed line of theshaft portion 11 a. A gear train is formed on a side opposite to thedistal end side illustrated in FIG. 12A within the drive shaft 11 sothat the drive shaft 11 can be rotated around the axis of the shaftportion 11 a of the drive shaft 11. The drive shaft 11 is connected to amotor serving as a drive source via the gear train.

In addition, the drive shaft 11 is arranged to protrude on a trajectoryof a movement for attachment and detachment at a substantially rightangle, with respect to a movement direction for attaching and detachingthe process cartridge 20 illustrated in FIG. 1 to and from the apparatusbody 10. Therefore, for the attachment and detachment of the processcartridge 20, it is necessary to attach and detach the shaft member 70to and from this drive shaft 11. Then, according to the above-describedend member 40, the attachment and detachment between the shaft member 70and the drive shaft 11 are facilitated. A specific aspect of theattachment and detachment will be described in detail later.

In a posture where the process cartridge 20 is mounted on the apparatusbody 10, the drive shaft 11 engages with the coupling member 71 of theshaft member 70 of the end member 40, thereby transmitting the rotationforce. FIG. 12B illustrates a scene where the coupling member 71 of theend member 40 engages with the drive shaft 11. As is understood fromFIG. 12B, in a posture where the drive shaft 11 and the coupling member71 engage with each other, the drive shaft 11 and the coupling member 71are arranged to abut onto each other so that the axis of the shaftportion 11 a of the drive shaft 11 coincides with the axis of thecoupling member 71. In this case, the pin 11 b of the drive shaft 11 isarranged inside the groove 74 a or the groove 74 b which the couplingmember 71 opposes (in FIG. 12B, arranged inside the groove 74 a). Thiscauses the coupling member 71 to be rotated to follow the rotation ofthe drive shaft 11, and causes the photosensitive drum unit 30 to berotated.

As described above, a posture where the rotation force is transmitted isa posture where the axis of the shaft portion 11 a and the axis of thecoupling member 71 are arranged coaxially and the pin 11 b is locatedinside the groove 74 a or the groove 74 b of the coupling member 71.

Next, an example of an operation of the drive shaft 11 and thephotosensitive drum unit 30 when the process cartridge 20 is mounted onthe apparatus body 10 will be described. FIGS. 13A and 13B illustrate aview for describing the example. FIG. 13A is a view illustrating onescene where the end member 40 engages with the drive shaft 11, and FIG.13B is a view illustrating another scene where the end member 40 engageswith the drive shaft 11. The operations are sequentially illustrated byusing FIGS. 13A and 13B, and rightward-leftward direction in the drawingpaper represents an extending direction of the axis. In addition, theseare the scenes where the process cartridge 20 is moved to the lower sidein the drawing paper and is mounted on the apparatus body 10.

As illustrated in FIG. 13A, the coupling member 71 of the shaft member70 is first arranged in a posture of being tilted to the drive shaft 11side. It is preferable that this posture be a posture where the shaftmember 70 is most tilted. If the process cartridge 20 is moved to thelower side in the drawing paper from this posture, the distal end of thedrive shaft 11 comes into contact with the inner side of the bottomportion 73 or the engagement wall 74 of the coupling member 71 so as tobe caught thereon. If the process cartridge 20 is further pressed intothe apparatus body 10, the drive shaft 11 which comes into contact withthe coupling member 71 so as to be caught thereon causes the shaftmember 70 tilted with respect to the axial direction to be pivotallymoved (swing) so that the shaft member 70 moves close to the axialdirection. Then, the pin 11 b is inserted into the groove 74 a.

Then, if the process cartridge 20 is further pressed into the apparatusbody 10 in the mounting direction, as illustrated in FIG. 13B, the axisof the tilted shaft member 70 coincides with the axis of the drive shaft11, and the axes of the drive shaft 11, the shaft member 70, the bearingmember 41, and the photosensitive drum 35 coincide with one another,thereby adopting the posture illustrated in FIG. 12B. This causes therotation force to be properly applied from the drive shaft 11 to theshaft member 70, the bearing member 41, and the photosensitive drum 35.The rotation force is finally applied to the process cartridge 20.

In contrast, an operation of the drive shaft 11 and the photosensitivedrum unit 30 when the process cartridge 20 is detached from theapparatus body 10 may be performed by reversing the above-describedorder.

As described above, the process cartridge 20 can be detached from theapparatus body 10 so as to be pulled out in a direction different fromthe axial direction of the drive shaft 11 of the apparatus body 10. Inaddition, the process cartridge 20 can be mounted on the apparatus body10 so as to be pressed into the apparatus body 10.

Next, a second embodiment will be described. Herein, description will bemade by focusing on portions different from those of the processcartridge 20 according to the first embodiment. The same referencenumerals are given to elements common to those of the process cartridge20, and description thereof will be omitted.

FIG. 14 is a view for describing the second embodiment, and is aperspective view of an end member 140. FIG. 14 is a view illustrated inthe same viewpoint in FIG. 2B. The end member 140 is a member attachedto an end portion opposite to the lid member 36 within the end portionof the photosensitive drum 35, and includes a bearing member 141 and theshaft member 70. The shaft member 70 is the same as the above-describedone.

The bearing member 141 is a member fixed to the end portion of thephotosensitive drum 35. FIG. 15 illustrates an exploded perspective viewof the bearing member 141. As is understood from FIG. 15, the bearingmember 141 includes a body 145 and an intermediate member 160.Hereinafter, the body 145 and the intermediate member 160 will berespectively described.

FIG. 16A illustrates a view when the body 145 is viewed from a side intowhich the intermediate member 160 is inserted, and FIG. 16B illustratesa perspective view when the body 145 is viewed from an angle differentfrom that in FIG. 15, respectively. In addition, FIG. 17 illustrates across-sectional view taken along the axis including a line illustratedby XVII-XVII in FIGS. 15, 16A, and 16B. Furthermore, FIG. 18Aillustrates a cross-sectional view taken along the axis including a lineillustrated by XVIIIa-XVIIIa in FIGS. 15, 16A, 16B, and 17. Then, FIG.18B illustrates a cross-sectional view taken along the axis including aline illustrated by XVIIIb-XVIIIb in FIGS. 16A and 17.

In the present embodiment, as is understood from FIGS. 14 to 18, thebody 145 is different from the body 45 in a form of a bottom portion 149and a holding portion. Other elements such as the cylindrical body 46,the contact wall 47, and the gear 48 become the same as those of thebody 45 in the description, and thus, description thereof will beomitted here.

The bottom portion 149 extending in a rod shape in a radial direction ofthe cylindrical body 46 is disposed in a cylindrical inner side of thecylindrical body 46 so as to close at least a portion of the inner sideof the cylindrical body 46. Furthermore, a holding portion 150 isdisposed on an inner side opposite to a side fixed to the photosensitivedrum 35 across the bottom portion 149 within the inner side of thecylindrical body 46.

The holding portion 150 forms guide surfaces 151 and 152 serving as anintermediate member guide on the inner side of the cylindrical body 46.Therefore, the holding portion 150 is arranged so that two projections150 a protrude from the inner surface of the cylindrical body 46 towardthe axis of the cylindrical body 46 and face each other. A groove 150 bis formed between the two projections 150 a.

A form of the holding portion 150 will be further described in detail.

As is well understood from FIGS. 16A and 16B, the two projections 150 aare arranged to face each other, and a gap is formed therebetween,thereby configuring the groove 150 b. In addition, the projection 150 ahas a concave portion 150 c so that a sphere having the center on theaxis of the cylindrical body 46 within the projection 150 a is partiallyhollowed. A spherical surface of the concave portion 150 c has a shapewhich enables the spherical body 90 of the shaft member 70 to beaccommodated therein. However, the concave portion 150 c may notnecessarily have the spherical surface.

Furthermore, a guide member insertion groove 150 d which extends in theradial direction orthogonal to the radial direction of the cylindricalbody 46 in which the groove 150 b extends is formed on the bottom of theconcave portion 150 c. The guide member insertion groove 150 d has aform which enables a guide member 165 of the intermediate member 160 (tobe described later) to be inserted.

In addition, as is well understood from FIGS. 17 and 18B, a surface isalso formed on a side opposite to the concave portion 150 c within theprojection 150 a (that is, a side opposing the bottom portion 149 withinthe holding portion 150). As is understood from FIG. 18B, the surfacehas an arc shape. These serve as guide surfaces 151 and 152. The guidesurfaces 151 and 152 have a curved surface formed so as to be curvedalong the extending direction of the groove 150 b. The guide member 165of the intermediate member 160 slides on the guide surfaces 151 and 152,thereby causing the shaft member 70 to swing. The swing will bedescribed later.

Therefore, the guide member insertion groove 150 d formed on the bottomportion of the concave portion 150 c is a groove which causes theconcave portion 150 c and a rear surface (surface on which the guidesurfaces 151 and 152 are present) of the holding portion 150 tocommunicate with each other, and which causes the guide member 165 toreach the guide surfaces 151 and 152.

It is preferable that the holding portion 150 having this form befurther formed as follows.

The groove width of the groove 150 b is not particularly limited, but itis preferable that the width be arranged to be approximately the same asthe thickness of the intermediate member 160. This can suppress thelooseness of the shaft member 70.

A shape of the inner surface of the concave portion 150 c is notparticularly limited as long as the shape enables the proximal endportion of the shaft member 70 to be accommodated therein. However, whenthe proximal end portion of the shaft member 70 is the spherical body90, it is preferable to provide a curved surface having the same radiusas that of the spherical body 90. This also prevents the looseness ofthe shaft member 70.

It is preferable that the guide member 165 of the intermediate member160 can be inserted into the guide member insertion groove 150 d, andthat the guide member insertion groove 150 d adopt a snap-fit(interference-fit in the entrance portion) structure with respect to theguide member 165. This can prevent the intermediate member 160 fromslipping out from the body 145. For example, the snap-fit structureincludes snap-fit structures 150 e and 150 f which are pieces protrudingfrom a wall surface of the guide member insertion groove 150 d.

The guide surfaces 151 and 152 are surfaces for guiding the intermediatemember 160 so that the shaft member 70 properly swings, and surfaces fordetermining the swing of the shaft member 70. Therefore, it ispreferable that the guide surfaces 151 and 152 have an arc shape in across section illustrated in FIG. 18B from a viewpoint that stable swingcan be obtained. That is, it is preferable that the guide surfaces 151and 152 have an arc shape around the center of the swing of the shaftmember. This enables a smooth swing. In addition, in the presentembodiment, an arc of the concave portion 150 c is also configured to bean arc which is concentric with the guide surfaces 151 and 152.

A material configuring the body 145 is the same as that of theabove-described body 45.

Referring back to FIG. 15, the intermediate member 160 will bedescribed. As is understood from FIG. 15, the intermediate member 160 isan annular member which is partially cut out. FIGS. 19A to 19Cillustrate the intermediate member 160. FIG. 19A is a perspective view,FIG. 19B is a front view, and FIG. 19C is a cross-sectional view takenalong a line illustrated by XIXc-XIXc in FIG. 19B.

The intermediate member 160 has an annular shape in which a cutoutportion 160 a is partially disposed.

In the intermediate member 160, an outer peripheral portion thereof isarranged in the groove 150 b included in the holding portion 150 of thebody 145. Therefore, the outer diameter of the intermediate member 160has a size which enables the intermediate member 160 to be inserted intothe groove 150 b.

In contrast, the proximal end portion of the shaft member 70 is arrangedon an annular inner side of the intermediate member 160. Accordingly,the annular inner side may have a size and a form which can accommodatethe proximal end portion inside the intermediate member 160. In thepresent embodiment, the proximal end portion of the shaft member 70 isthe spherical body 90. Accordingly, the inner diameter of theintermediate member 160 can be configured to be the same as the diameterof the spherical body 90. In addition, as is understood from FIG. 19C,the inner peripheral surface of the intermediate member 160 is alsocurved in an arc shape in a direction along the axis of the ring(vertical direction on the drawing paper in FIG. 19C). The curve canmatch the curve formed by the diameter of the spherical body 90. Thisenables the intermediate member 160 and the spherical body 90 to be moresuitably combined with each other.

Then, the size (that is, thickness) in the direction along the axis ofthe ring of the intermediate member 160 is substantially the same as thewidth of the guide groove 150 b formed in the holding portion 150 of theabove-described body 145. This can prevent the looseness.

The cutout portion 160 a of the intermediate member 160 has a size and ashape which enable at least the rotary shaft 85 (refer to FIGS. 8A and8B) of the shaft member 70 to be arranged thereinside.

Two grooves 161 and 162 extending outward from the inner peripheralsurface of the ring are disposed in the intermediate member 160. The twogrooves 161 and 162 are disposed to oppose each other along the diameterof the intermediate member 160. Both ends of the rotation forcetransmission pin 95 (refer to FIGS. 8A and 8B) of the shaft member 70are respectively inserted into the grooves 161 and 162. Therefore, ashape and arrangement of the grooves 161 and 162 are configured so thatthe end portions of the rotation force transmission pin 95 can berespectively inserted into the grooves 161 and 162.

In addition, it is preferable that pieces 161 a and 162 a remain in oneof the grooves 161 and 162 in the direction along the axis of the ringof the intermediate member 160, and that the grooves 161 and 162 do notpenetrate in the direction along the axis. In this manner, when theshaft member 70 is assembled to the intermediate member 160 and therotation force is applied to the shaft member 70 from the apparatus body10, the rotation force transmission pin 95 is caught on by the pieces161 a and 162 a so that the rotation fore can be properly transmitted tothe intermediate member 160. Therefore, in view of the rotation of therotation force transmission pin 95, as is well understood from FIGS. 19Ato 19C, the piece 161 a of the groove 161 and the piece 162 a of thegroove 162 are disposed on different sides in the axial direction of theintermediate member 160.

If a distal end of the rotation force transmission pin 95 extends toreach the inside of the guide groove 150 b of the holding portion 150 ofthe body 145, the distal end of the rotation force transmission pin 95is caught on by a lateral wall of the guide groove 150 b when rotated.Accordingly, since the rotation force can be transmitted, the pieces 161a and 162 a may not be necessarily disposed.

In addition, an opening portion opposing the pieces 161 a and 162 awithin the grooves 161 and 162 may be slightly narrowed as compared tothe inside of the groove. Specifically, the opening portion can beconfigured to have an opening which is slightly smaller than thediameter of the rotation force transmission pin 95. In this manner, therotation force transmission pin 95 which has entered the inside of thegrooves 161 and 162 once is less likely to slip out from the grooves 161and 162 by the narrowed opening portion.

Furthermore, the guide member 165 which functions as a guided portionrespectively from annular-shaped front and rear surfaces and extendsalong the axial direction of the ring is arranged so as to protrude inthe intermediate member 160. In the present embodiment, the guide member165 is a columnar pin. A position where the guide member 165 is arrangedis not particularly limited. As will be described later, the guidemember 165 may be arranged at a position where the guide member 165 canslide on the guide surfaces 151 and 152 when the intermediate member 160is arranged in the body 145. In addition, a shape of the guide member165 is not limited to the column. The guide member 165 may have across-sectional shape of a quadrangular column, a triangular column, orothers.

A material configuring the intermediate member 160 is not particularlylimited, but it is possible to use a resin such as polyacetal,polycarbonate, and PPS. Here, in order to improve rigidity of themember, glass fibers or carbon fibers may be mixed with the resin,depending on load torques. In addition, in order to obtain a smoothswing operation when the intermediate member 160 is attached to the body145, sliding performance may be improved by causing the resin to containat least one type among fluorine, polyethylene, and silicone rubber. Inaddition, the resin may be coated with fluorine, or lubricant may beapplied to the resin.

The bearing member 141 and the shaft member 70 are combined with eachother as follows so as to configure the end member 140. Description ofthis combination will further facilitate understanding of a formincluded in the bearing member 141 and the shaft member 70, or a formand a size of the members.

FIG. 20 illustrates a cross-sectional view of the end member 140 whichis taken along line XX-XX illustrated in FIG. 14, and FIG. 21Aillustrates a cross-sectional view of the end member 140 which is takenalong line XXIa-XXIa illustrated in FIG. 14, respectively. FIG. 21Billustrates a view focusing on a positional relationship between thebody 145 and the guide member 165 included in the intermediate member160, within a cross section of the end member 140 which is taken alongline XXIb-XXIb illustrated in FIG. 20. Therefore, the shaft member 70 isomitted in FIG. 21B.

In addition, FIG. 22 illustrates an example of a posture where the shaftmember 70 is tilted in a viewpoint illustrated in FIG. 20, FIG. 23Aillustrates an example of a posture where the shaft member 70 is tiltedin a viewpoint illustrated in FIG. 21A, and FIG. 23B illustrates anexample of a posture where the shaft member 70 is tilted in the postureillustrated in FIG. 21B, respectively.

As is understood particularly well from FIG. 21A, the spherical body 90is arranged inside the ring of the intermediate member 160, and therotation force transmission pin 95 is inserted into the grooves 161 and162 of the intermediate member 160. In this manner, the intermediatemember 160 and the shaft member 70 are combined with each other.Therefore, as illustrated by arrow XXII in FIG. 22, the shaft member 70can swing around the axis of the rotation force transmission pin 95 withrespect to the intermediate member 160.

In contrast, as is well understood from FIGS. 20 and 21B, the guidemember 165 of the intermediate member 160 is arranged at a positionwhere the guide member 165 penetrates the guide member insertion groove150 d, reaches the bottom portion 149 side, and can slide on the guidesurfaces 151 and 152. Then, as will be described later, the guide member165 slides on the guide surfaces 151 and 152 so that the intermediatemember 160 is guided. As a result, as illustrated by arrow XXIIIa inFIG. 23A, the intermediate member 160 can be rotated inside the body145.

In addition, as is well understood from FIGS. 20, 21A, and 21B, theintermediate member 160 is arranged inside the groove 150 b so that thethickness direction of the intermediate member 160 is the groove widthdirection of the groove 150 b formed in the holding portion 150.Therefore, a portion of the intermediate member 160 is arranged insidethe groove 150 b, and the intermediate member 160 can be moved so as toslide inside the groove 150 b.

As described above, in the end member 140 of the present embodiment, theintermediate member 160 is held by the guide surfaces 151 and 152 formedin the body 145 so as not to slip out, and the shaft member 70 is heldby the intermediate member 160 so as not to slip out. More specifically,the guide member 165 engages with the guide surfaces 151 and 152 of thebody 145, thereby regulating a movement of the shaft member 70 in thedirection in which the shaft member 70 is pulled out from the body 145.

In this manner, the shaft member 70 is not directly held by the body145. However, the proximal end portion 90 of the shaft member 70 isconfigured so that a movement thereof in directions other than thedirection in which the shaft member 70 is pulled out from the body 145is regulated by the concave portion 150 c (for example, refer to FIGS.16A and 16B) formed in the holding portion 150 of the body 145.

It is possible to adjust a clearance (so-called “slack”) between theshaft member 70 and the body 145 by using a relative positionalrelationship between the guide surfaces 151 and 152 and the guide member165 and a dimensional relationship between the proximal end portion 90and the concave portion 150 c.

This assembly work of the end member 140 can be carried out by firstarranging the shaft member 70 in the intermediate member 160 andattaching the intermediate member 160 to the body 145. In this case,when the guide member 165 of the intermediate member 160 is caused topenetrate the guide member insertion groove 150 d, the assembly work canbe carried out through elastic deformation using a weak force.Therefore, it is possible to assemble the shaft member 70 to the bearingmember 141 easily and with increased productivity. In addition, not onlythe assembly work is facilitated, but also the detachment work issimilarly facilitated. Accordingly, the reuse is also facilitated.Particularly, in this case, it is not necessary to deform the shaftmember 70 during the insertion and the detachment. Accordingly, there isno more possibility of damage. In addition, since the detachment isfacilitated, workability can also be improved.

As described above, the shaft member 70 is arranged inside the bearingmember 141, thereby enabling the shaft member 70 to swing as illustratedin FIGS. 22, 23A, and 23B. That is, in a viewpoint illustrated in FIG.22, the shaft member 70 can swing around the axis of the rotation forcetransmission pin 95 as illustrated by arrow XXII. In contrast, in aviewpoint illustrated in FIG. 23A, the shaft member 70 can swing tofollow the rotation of the intermediate member 160 as illustrated byarrow XXIIIa. In this case, as illustrated in FIG. 23B, the guide member165 slides on the guide surfaces 151 and 152. In this manner, therotation of the intermediate member 160 is guided, and based on thisguidance, the shaft member 70 can swing.

The swing illustrated in FIG. 22 and the swing illustrated in FIG. 23Aare swings in a direction in which the swings are orthogonal to eachother.

In addition, when the driving force is received from the apparatus body10, the shaft member 70 receives the rotation force acting around theaxis as illustrated by arrow XXc in FIGS. 20 and 21A. In this case, bothend portions of the rotation force transmission pin 95 of the shaftmember 70 press the pieces 161 a and 162 a (refer to FIG. 19B) of theintermediate member 160, and the intermediate member 160 is caught on bythe lateral wall of the groove 150 b of the body 145. In this manner,the rotation force can be transmitted to the photosensitive drum 35.

If the distal end of the rotation force transmission pin 95 extends toreach the inside of the guide groove 150 b of the holding portion 150 ofthe body 145, even when the pieces 161 a and 162 a are not arranged, thedistal end of the rotation force transmission pin 95 is caught on by thelateral wall of the guide groove 150 b when rotated. In this case, therotation force can be transmitted without pressing the intermediatemember 160.

According to this end member 140, it is possible to obtain anadvantageous effect which is the same as that according to theabove-described end member 40.

The above-described configuration enables the shaft member 70 to bepivotally moved (swing), to transmit the rotation force, and to be heldby the bearing member 141. The end member 140 is attached to thephotosensitive drum 35 by inserting the end portion on a side where theshaft member 70 does not protrude within the end member 140 into thephotosensitive drum 35 after the end member 140 is assembled asillustrated in FIG. 14. This end member 140 properly applies therotation force to the photosensitive drum 35 when the process cartridge20 is mounted on the apparatus body 10, and enables the processcartridge 20 to be easily attached and detached.

Next, a third embodiment will be described. FIGS. 24A and 24B are viewsfor describing the third embodiment, and is a view illustrating anintermediate member 260. FIG. 24A is a perspective view, FIG. 24B is afront view, and FIG. 24C is a plan view.

In the present embodiment, a form of a portion with which the rotationforce transmission pin 95 of the shaft member 70 within the intermediatemember 260 is different from that of the intermediate member 160. Otherelements are the same as those of the above-described end member 140,and thus, the intermediate member 260 will be described here.

The intermediate member 260 is formed in a semi-annular shape in a frontview as illustrated in FIG. 24B, and grooves 261 and 262 extending inthe radial direction are formed on an end surface thereof. The groovewidth of the grooves 261 and 262 is approximately the same as thediameter of the rotation force transmission pin 95. Then, snap-fit(interference-fit in the entrance portion) structures 261 a and 262 aare formed on the end surface side of the intermediate member 260 in thegrooves 261 and 262. This enables the rotation force transmission pin 95of the shaft member 70 to engage with the grooves 261 and 262 withoutbeing detached therefrom. FIGS. 25A and 25B illustrate views fordescribing this configuration.

FIG. 25A is a perspective view illustrating a posture where the shaftmember 70 is combined and engaged with the intermediate member 260, andFIG. 25B is a cross-sectional view taken along the axis in FIG. 25A. Asis understood from FIGS. 25A and 25B, at least a portion of both endportions of the rotation force transmission pin 95 is arranged insidethe grooves 261 and 262. In addition, a configuration is adopted so thatthe snap-fit structures 261 a and 262 a cause the rotation forcetransmission pin 95 not to slip out from the grooves 261 and 262.

According to this intermediate member 260, it is possible to more easilyattach the shaft member 70 to the intermediate member 260. Therefore,for example, when the photosensitive drum unit 30 is assembled, thebearing member in which the intermediate member 260 has been alreadymounted on the body is first fixed to the end portion of thephotosensitive drum 35. Thereafter, the shaft member 70 can be mountedon the intermediate member 260 of the bearing member. According to thisassembly, it is possible to attach the unstably swinging shaft member 70individually and lastly. Therefore, it is possible to improveconvenience in the assembly.

In addition, in the snap-fit structures 261 a and 262 a for regulatingthe detachment (disengagement) of the rotation force transmission pin 95and the snap-fit structures 150 e and 150 f of the guide memberinsertion groove 150 d for regulating the detachment (disengagement) ofthe guide member 165, a degree of a force needed to pull out (disengage)the rotation force transmission pin 95 and the guide member 165 isadjusted. In this manner, it is possible to cause the intermediatemember to remain in the body side when the shaft member 70 is detached,and to detach the intermediate member 260 together with the shaft member70 from the body. For example, when the body 145 and the intermediatemember 260 are combined for reuse, an interference-fit condition of thesnap-fit structures 261 a and 262 a is adjusted to be relatively weakerthan an interference-fit condition of the snap-fit structures 150 e and150 f of the guide member insertion groove 150 d, and it is no longernecessary to separately manage the intermediate member 260 and the body145 since the intermediate member 260 remains in the body 145.Therefore, the reuse is further facilitated, and the workability isimproved. On the other hand, when only the body 145 or only theintermediate member 260 is reused, if the intermediate member 260 doesnot remain in the body 145, man-hours are reduced in separating theintermediate member and the body later. Therefore, the interference-fitcondition of the snap-fit structures 261 a and 262 a may be adjusted tobe relatively stronger than the interference-fit condition of thesnap-fit structures 150 e and 150 f of the guide member insertion groove150 d, thereby improving the workability.

Next, a fourth embodiment will be described. In the fourth embodiment, aform of a body 345 is different from the form of the above-describedbody 145. Other elements can be similarly considered, and thus, the body345 will be described here. The same reference numerals are given tothose which are considered to be the same as the members and elementswhich have been described hitherto, and description thereof will beomitted.

FIG. 26A illustrates a plan view when the body 345 is viewed from a sideinto which the intermediate member 160 is inserted, and FIG. 26Billustrates a perspective view of the body 345. In addition, FIG. 27illustrates a cross-sectional view along the axis including a lineillustrated by XXVII-XXVII in FIGS. 26A and 26B. Furthermore, FIG. 28Aillustrates a cross-sectional view along the axis including a lineillustrated by XXVIIIa-XXVIIIa in FIGS. 26A, 26B, and 27. Then, FIG. 28Billustrates a cross-sectional view along the axis including a lineillustrated by XXVIIIb-XXVIIIb in FIGS. 26A, 26B, and 27.

The bottom portion 149 extending in a rod shape in the radial directionof the cylindrical body 46 is disposed in a cylindrical inner side ofthe cylindrical body 46 so as to close at least a portion of the innerside of the cylindrical body 46. Furthermore, a holding portion 350 isdisposed on an inner side opposite to a side fixed to the photosensitivedrum 35 across the bottom portion 149 within the inner side of thecylindrical body 46.

The holding portion 350 forms guide surfaces 351 and 352 serving as anintermediate member guide on the inner side of the cylindrical body 46.Therefore, the holding portion 350 is arranged so that two projections350 a protrude from the inner surface of the cylindrical body 46 towardthe axis of the cylindrical body 46 and face each other. A groove 350 bis formed between the two projections 350 a.

A form of the holding portion 350 will be further described in detail.

As is well understood from FIGS. 26A and 26B, the two projections 350 aare arranged to face each other, and a gap is formed therebetween,thereby configuring the groove 350 b. In addition, the projection 350 ahas a concave portion 350 c so that a sphere having the center on theaxis of the cylindrical body 46 within the projection 350 a is partiallyhollowed. A portion of the spherical surface of the concave portion 350c has a shape which enables the spherical body 90 of the shaft member 70to be accommodated therein. However, the concave portion 350 c may notnecessarily have the spherical surface.

Then, guide surfaces 351 and 352 are formed on a surface opposite to theconcave portion 350 c within the projection 350 a.

Furthermore, in the holding portion 350, a guide member insertion groove350 d is disposed between the cylindrical body 46 and the concaveportion 350 c within the end surface of the projection 350 a. The guidemember insertion groove 350 d is disposed so as to cause the concaveportion 350 c side to communicate with the guide surfaces 351 and 352side, and further one end thereof is open through the groove 350 b. Asize and a shape of the guide member insertion groove 350 d are formedso that the guide member 165 of the intermediate member 160 can beinserted into the guide member insertion groove 350 d.

In the present embodiment, the guide member insertion grooves 350 d arerespectively disposed on one side and the other side of the groove 350b. However, the guide member insertion grooves 350 d are not necessarilydisposed on both sides. The guide member insertion groove 350 d may bedisposed on any one side. In the above-described body 145, the guidemember insertion groove 150 d is disposed on the bottom of the concaveportion 150 c. However, in the present embodiment, the guide memberinsertion groove 350 d is disposed in the end portion of the groove 350b as described above. This can eliminate a possibility that the guidemember insertion groove 350 d influences the movement of theintermediate member 160. That is, as will be described later, when theguide member 165 of the intermediate member 160 moves along the guidesurfaces 351 and 352 (refer to FIG. 27) of the holding portion 350, theguide member 165 is not caught on by the guide member insertion groove350 d. Accordingly, a smooth movement is allowed. In addition, even whenthe shaft member 70 is pulled carelessly, it is possible to prevent theshaft member 70 from being detached unintentionally.

From a viewpoint of manufacturing the end member so that a mold isarranged, it is also possible to dispose a groove penetrating in theaxial direction in any one of the projections 350 a (not illustrated).In this case, the swing of the shaft member 70 is smoothly maintained byforming the groove to be thinner than the guide member 165.

As described above, a surface is also formed on a side opposite to theconcave portion 350 c within the projection 350 a (that is, a sideopposing the bottom portion 149 within the holding portion 350). As isunderstood from FIG. 28B, the surface has an arc shape. These serve asguide surfaces 351 and 352. The guide surfaces 351 and 352 have a curvedsurface formed so as to be curved along the extending direction of thegroove 350 b. The guide member 165 of the intermediate member 160 slideson the guide surfaces 351 and 352, thereby causing the shaft member 70to swing similarly as described above.

Therefore, the guide member insertion groove 350 d causes the concaveportion 350 c side of the projection 350 a and a rear surface (surfaceon which the guide surfaces 351 and 352 are present) of the holdingportion 350 to communicate with each other, and causes the guide member165 to reach the guide surfaces 351 and 352.

It is preferable that the holding portion 350 having this form befurther formed as follows.

The groove width of the groove 350 b is not particularly limited, but itis preferable that the width be arranged to be approximately the same asthe thickness of the intermediate member 160. This can suppress thelooseness of the shaft member 70.

A shape of the inner surface of the concave portion 350 c is notparticularly limited as long as the shape enables the proximal endportion of the shaft member 70 to be accommodated therein. However, whenthe proximal end portion of the shaft member 70 is the spherical body90, it is preferable to provide a curved surface having the same radiusas that of the spherical body 90. This also prevents the looseness ofthe shaft member 70.

It is preferable that the guide member 165 of the intermediate member160 can be inserted into the guide member insertion groove 350 d, andthat the guide member insertion groove 350 d adopt a snap-fit(interference-fit in the entrance portion) structure with respect to theguide member 165.

The guide surfaces 351 and 352 are surfaces for determining the swing ofthe shaft member 70. Therefore, it is preferable that the guide surfaces351 and 352 have an arc shape in a cross section illustrated in FIG. 28Bfrom a viewpoint that stable swing can be obtained. That is, it ispreferable that the guide surfaces 351 and 352 have an arc shape aroundthe center of the swing of the shaft member 70. This enables smoothswing. In addition, in the present embodiment, an arc of the concaveportion 350 c is also configured to be an arc which belongs to the samecircle to which the guide surfaces 351 and 352 belong.

FIGS. 29 and 30 illustrate a view in which the intermediate member 160is combined with the body 345 so as to configure a bearing member 341.FIG. 29 is a perspective view, FIG. 30A is a view illustrated by usingthe same viewpoint in FIG. 28A, and FIG. 30B is a view illustrated byusing the same viewpoint in FIG. 28B. FIG. 31 is a view illustrating astate of a movement of the guide member 165 when the intermediate member160 is combined with the body 345.

As is understood from these drawings, in the bearing member 341, theguide member 165 of the intermediate member 160 is arranged at aposition where the guide member 165 penetrates the guide memberinsertion groove 350 d, reaches the bottom portion 149 side(sequentially as illustrated by a straight line arrow in FIG. 31), andcan slide on the guide surfaces 351 and 352. Then, similar to theabove-described bearing member 141, the guide member 165 slides on theguide surfaces 351 and 352. In this manner, the intermediate member 160is guided. As a result, the intermediate member 160 can be rotatedinside the body 345.

In addition, as is well understood from FIG. 29, the intermediate member160 is arranged inside the groove 350 b so that the thickness directionof the intermediate member 160 is the groove width direction of thegroove 350 b formed in the holding portion 350. Therefore, a portion ofthe intermediate member 160 can be arranged inside the groove 350 b, andthe intermediate member 160 can be rotated (swung) so as to slide insidethe groove 350 b.

Furthermore, in the bearing member 341 of the present embodiment, as iswell understood from FIGS. 29 and 30A, when both ends of theintermediate member 160 adopt a posture of being arrayed side by side inthe direction orthogonal to the axis of the body 345 (radial directionof the body 345), the grooves 161 and 162 of the intermediate member 160adopt a structure in which the grooves 161 and 162 of the intermediatemember 160 are exposed by projecting from the projection 350 a formed inthe holding portion 350 of the body 345. Therefore, in the presentembodiment, the shaft member 70 can be attached after the intermediatemember 160 is combined with the body 345. Therefore, it is possible tocarry out the assembly work more easily and with increased productivity.In addition, the detachment work of only the shaft member 70 is alsofurther facilitated. Accordingly, the reuse is also facilitated.Particularly, in this case, it is not necessary to deform the shaftmember 70 during the insertion and the detachment. Accordingly, there isno more possibility of damage. In addition, since the detachment isfacilitated, the workability can also be improved.

As described above, the shaft member 70 is combined with theintermediate member 160 of the bearing member 341 according to thepresent embodiment, thereby configuring an end member. Then, even inthis end member, the intermediate member 160 is held by the guidesurfaces 351 and 352 formed in the body 345 so as not to slip out, andthe shaft member 70 is held by the intermediate member 160 so as not toslip out. Therefore, the shaft member 70 is not directly held by thebody 345. Then, the end member in which the shaft member 70 is combinedwith the bearing member 341 can also be operated similar to theabove-described end member 140.

FIG. 32 is a cross-sectional view illustrating a scene in which theshaft member 70 is combined with the bearing member 341 and the shaftmember 70 is most tilted. As is understood from FIG. 32, even when theshaft member 70 is tilted, the rotary shaft 85 of the shaft member 70comes into contact with the body 345 of the bearing member 341 beforethe guide member 165 reaches the guide member insertion groove 350 d.Accordingly, the shaft member 70 is no longer tilted. Therefore, thereis no possibility that the intermediate member 160 slips out from thebody 345. In addition, even when the shaft member 70 is pulled, theguide member 165 cannot reach the guide member insertion groove 350 d.Therefore, unintentional detachment does not occur.

Then, in a swing range of the shaft member 70, when the guide member 165of the intermediate member 160 moves along the guide surfaces 351 and352, the guide member 165 is not caught on by the guide member insertiongroove 350 d. Accordingly, the smooth movement is allowed.

FIGS. 33A and 33B are views for describing a bearing member 341′ havinga body 345′ according to a modification example of the body 345. FIG.33A is a perspective view of the bearing member 341′, and FIG. 33B is anenlarged view of a portion in FIG. 33A. In the present example, whenboth ends of the intermediate member 160 adopt a posture of beingarrayed side by side in the direction orthogonal to the axis of the body345′ (radial direction of the body 345′), a projection 350 a′ extends inthe direction along the axis so that even the end portion of theintermediate member 160 is hidden inside a groove 350 b′. However, aportion of the projection 350 a′ is cut out and a space 350 f′ is formedso that the shaft member 70 can be engaged with the grooves 161 and 162of the intermediate member 160. The projection 350 a′ is formed so as tolead to the grooves 161 and 162 of the intermediate member 160 from thespace 350 f′.

FIG. 34 is a view for describing a bearing member 341″ having a body345″ according to another modification example of the body 345. FIG. 34is a perspective view of the bearing member 341″. In the presentexample, a space 350 f″ which is larger than the space 350 f′ of thebody 345′ is formed.

According to the bodies 345′ and 345″, the spaces 350 f′ and 350 f″ensure that the shaft member 70 is easily attached and detached, and canincrease a contact portion between the intermediate member 160 and thebodies 345′ and 345″ on the opposite side of the spaces 350 f′ and 350f″. Therefore, it is possible to disperse a load during rotation.

Next, a fifth embodiment will be described. In the fifth embodiment, aholding portion 450 of a body 445 is different from that according tothe above-described fourth embodiment, and a guide member 465 of anintermediate member 460 is different from that according to theabove-described fourth embodiment. Other elements can be similarlyconsidered, and thus, the body 445 and the intermediate member 460 willbe described here by focusing on elements which are different from thosein the fourth embodiment. Then, the same reference numerals are given tothose which are considered to be the same as the members and elementswhich have been described hitherto, and description thereof will beomitted.

FIGS. 35A and 35B illustrate a view for describing the body 445. FIG.35A is a view illustrated by using the same viewpoint in FIG. 28A, andFIG. 35B is a view illustrated by using the same viewpoint in FIG. 28B.In addition, FIG. 36A illustrates a perspective view of the intermediatemember 460, FIG. 36B illustrates a front view of the intermediate member460, and FIG. 36C illustrates a plan view of the intermediate member460, respectively.

As is understood from FIGS. 35A and 35B, similar to the holding portion350, the guide member insertion groove 350 d is also disposed in theholding portion 450 included in the body 445. In the holding portion450, a return piece 450 e extending to the guide surfaces 351 and 352side (bottom portion 149 side) is arranged from an edge continuous withthe guide surface 351 within an edge of the guide member insertiongroove 350 d. This causes an internal corner portion 450 f which is opento the guide surfaces 351 and 352 side to be formed between the returnpiece 450 e and the guide surfaces 351 and 352. Then, the internalcorner portion 450 f does not appear when the guide member insertiongroove 350 d is viewed from the concave portion 350 c side.

In contrast, as is understood from FIGS. 36A to 36C, a guide member 465(guided portion) whose shape is different from that in the intermediatemember 160 is disposed in the intermediate member 460. That is, in thepresent embodiment, the guide member 465 has a substantially triangularcolumn shape, and a distal end thereof is tapered in a cone shape.

Therefore, projections 465 b having apexes of a triangle in both ends ofa surface 465 a in contact with the guide surfaces 351 and 352 of theholding portion 450 are formed in the guide member 465.

According to the above-described configuration, the intermediate member460 is further less likely to slip out from the body 445 after theintermediate member 460 is combined with the body 445. FIGS. 37A and 37Billustrate views for the description. FIG. 37A illustrates across-sectional view of a scene where the intermediate member 460 iscombined with the body 445, and FIG. 37B illustrates a cross-sectionalview of a scene where swing of the shaft member 70 causes theintermediate member 460 to swing together, respectively.

First, a scene is considered where the intermediate member 460 isattached to the body 445. In the scene, as illustrated by arrow XXXVIain FIG. 37A, the guide member 465 of the intermediate member 460 isarranged on the guide surfaces 351 and 352 side by penetrating the guidemember insertion groove 350 d from the concave portion 350 c side. Inthis case, as described above, the return piece 450 e causes theinternal corner portion 450 f to be oriented so as not to interfere withthe insertion of the guide member 465. Therefore, the intermediatemember 460 can be attached to the body 445 smoothly as usual.

Next, a scene is considered where the shaft member 70 and theintermediate member 460 swing after the intermediate member 460 and theshaft member 70 are attached to the body 445. In the scene, asillustrated by arrow XXXVIIb in FIG. 37B, the guide member 465 of theintermediate member 460 is guided and moved by the guide surface 351 ofthe body 445. In this case, if the swing becomes large and the guidemember 465 reaches the return piece 450 e, the projection 465 b of theguide member 465 enters the internal corner portion 450 f formed by theguide surfaces 351 and 352 and the return piece 450 e. Therefore, theguide member 465 can no longer move. Accordingly, there is nopossibility that the guide member 465 slips out from the guide memberinsertion groove 350 d.

As described above, according to the present embodiment, there isprovided a function as the above-described end member. The attachmentwork between the intermediate member 460 and the body 445 can besmoothly carried out. Furthermore, it is possible to more reliablyprevent the intermediate member 460 from slipping out from the body 445unintentionally. For example, even when the body 445 and theintermediate member 460 are transported in an assemble state, there isno possibility that vibrations generated during the transport cause theintermediate member 460 to slip out therefrom.

In the present embodiment, the guide member 465 of the intermediatemember 460 is configured to have the triangular column shape asdescribed above, thereby showing a shape in which the guide member 465is likely to enter the internal corner portion 450 f. However, the shapeof the guide member is not particularly limited as long as the shape ofthe guide member regulates the movement (rotation) by the guide memberentering the internal corner portion.

Hitherto, embodiments and examples have been described in which all thedescribed end members are arranged in the end portion of thephotosensitive drum 35 and the photosensitive drum unit is formedaccording to this configuration. In contrast, as described withreference to FIG. 2, the process cartridge additionally includes thedeveloping roller unit having the columnar rotary body or the chargingroller unit. Therefore, all the end members according to theabove-described embodiments and modification examples can be applied tothe developing roller unit or the charging roller unit, instead of beingarranged in the photosensitive drum. In this manner, the developingroller unit or the charging roller unit can receive the rotation drivingforce from the apparatus body. As one embodiment, FIG. 38 illustrates adeveloping roller unit 523 including the end member 40. FIG. 38 alsoillustrates a perspective view of the developing roller unit 523 and aphotosensitive drum unit 530 which is arranged to be adjacent thereto.

The developing roller unit 523 includes a developing roller 524, aspacer ring 525, a lid member 526, a magnetic roller (not illustrated),and the end member 40. The end member 40 is configured as describedabove. In addition, those which are known can be applied to othermembers, but other members include the following configurations, forexample.

The developing roller 524 is a member in which an outer peripheralsurface of a columnar rotary body is coated with a developer layer. Inthe present embodiment, the developing roller 524 is a conductivecylinder made of aluminum, and is configured so that a materialconfiguring the developer layer is applied thereto.

The spacer ring 525 is an annular member which is arranged so as to windaround each outer peripheral surface in both ends of the developingroller 524, thereby holding a constant gap between the developing roller524 and the photosensitive drum 35. The thickness of the spacer ring 525is approximately 200 μm to 400 μm.

Similar to the above-described lid member 36, the lid member 526 is abearing which is arranged on one end side of the developing roller 524,and which causes the developing roller 524 to be rotated around the axisin one end of the developing roller unit 523.

The magnetic roller is arranged inside the developing roller 524, andthus is not illustrated in FIG. 38. However, the magnetic roller is aroller formed of a magnetic material or a resin containing the magneticmaterial, and multiple magnetic poles are arranged along the axis. Inthis manner, it is possible to deposit a developer on a surface of thedeveloping roller 524 by using a magnetic force.

The end member 40 is configured as described above, but is arranged inan end portion opposite to the end portion in which the lid member 526is arranged within the end portion of the developing roller 524. Herein,an example of applying the end member 40 has been described. However,without being limited thereto, any other end member already describedabove can also be applied.

In this case, for example, the photosensitive drum unit 530 can beconfigured as follows. That is, the photosensitive drum unit 530includes the photosensitive drum 35, and lid members 36 and 540 whichserve as a bearing for rotating the photosensitive drum 35 around theaxis in each portion of both ends of the photosensitive drum 35. In thiscase, one lid member 540 includes a gear portion 541 which meshes with agear 48 of the end member 40 arranged in the developing roller unit 523and receives the rotation force.

As described above, each end member may be a configuring member includedin the developing roller unit. In this case, the end member is alsooperated similarly to when included in the photosensitive drum unit.

According to the present invention, there are provided a bearing member,an end member, a photosensitive drum unit, a developing roller unit, aprocess cartridge, an intermediate member, and a bearing member bodywhich ensure sufficiently smooth swing of a shaft member.

Hereinafter, some aspects of the present invention will be described.Here, for ease of understanding, reference numerals in the drawings aregiven in parentheses, but the present invention is not limited thereto.

The present invention includes a bearing member (41, 141) configured tobe arranged in an end portion of a columnar rotary body (35, 524),wherein a shaft member (70) is attachable to the bearing member, thebearing member including: a body (45, 145) that includes a cylindricalbody (46) and a holding portion (50, 150) which is arranged inside thecylindrical body; and an intermediate member (60, 160, 260) that is heldby the holding portion of the body, wherein the holding portion includesan intermediate member guide (51, 52, 53, 54, 151, 152) which guides theintermediate member so that the intermediate member rotates, and theintermediate member includes a portion in which the shaft member isarranged.

Here, the “columnar rotary body” is a general idea including a rotarybody which has a solid round bar shape and rotates around an axis line,and a rotary body which has a cylindrical hollow shape and rotatesaround an axis line.

In an aspect of the bearing member (41) according to the presentinvention, the intermediate member guide (51, 52, 53, 54) is a guidegroove into which an outer peripheral portion of the intermediate memberis inserted, wherein the guide groove slides and guides the outerperipheral portion, and at least a portion on a bottom surface of theguide groove is a curved surface.

In an aspect of the bearing member (41) according to the presentinvention, the curved surface on the bottom surface of the guide groove(51, 52, 53, 54) comes into contact with the outer peripheral portion ofthe intermediate member (60), thereby regulating a movement in adirection along an axis of the cylindrical body (46) of the intermediatemember.

In an aspect of the bearing member (141) according to the presentinvention, a protruding guide member (165) is disposed in theintermediate member (160, 260), the intermediate member guide (151, 152)is a guide surface on which the guide member slides, and at least aportion of the guide surface is a curved surface.

In an aspect of the bearing member (141) according to the presentinvention, a guide member insertion groove (150 d, 350 d) is disposed inthe holding portion (150) for causing the guide member (165) to reachthe guide surface (151, 152).

In an aspect of the bearing member (141) according to the presentinvention, the guide member insertion groove includes a snap-fitstructure which is a portion narrower than an outer shape of the guidemember.

In an aspect of the bearing member (141) according to the presentinvention, a groove (261, 262) into which a portion of a shaft member(70) is inserted is disposed in the intermediate member (260), and thegroove includes a snap-fit structure (261 a, 262 a) which is a portionnarrower than an outer shape of the inserted portion of the shaftmember.

In an aspect of the bearing member (141) according to the presentinvention, the snap-fit structure of the guide member insertion groove(150 d) can be disengaged with a force weaker than a force for thesnap-fit structure (261 a, 262 a) of the groove (261, 262) disposed inthe intermediate member (260).

In an aspect of the bearing member (141) according to the presentinvention, the snap-fit structure of the guide member insertion groove(150 d) needs to be disengaged with a force stronger than a force forthe snap-fit structure (261 a, 262 a) of the groove (261, 262) disposedin the intermediate member (260).

An end member (40, 140) according to the present invention includes: ashaft member (70); and the bearing member (41, 141), wherein the shaftmember includes: a rotary shaft (85); a rotation force receiving portion(71) which is included on one end side of the rotary shaft, which canengage with a rotation force applying portion of an image formingapparatus body, and which receives a rotation force from a drive shaftby maintaining an engaging posture thereof; a proximal end portion (90)which is arranged on the other end side of the rotary shaft; and arotation force transmission projection (95) which projects from theproximal end portion, wherein a groove (61, 62, 161, 162, 261, 262) withwhich the rotation force transmission projection engages is disposed inthe intermediate member, and the shaft member is assembled to theintermediate member by the rotation force transmission projectionengaging with the groove.

A photosensitive drum unit (30) according to the present invention isconfigured such that the columnar rotary body is a photosensitive drum(35), and the photosensitive drum unit includes the photosensitive drumand the end member (40, 140) which is arranged in at least one endportion of the photosensitive drum.

A developing roller unit (523) according to the present invention isconfigured such that the columnar rotary body is a developing roller(524), and the developing roller unit includes the developing roller andthe end member (40) which is arranged in at least one end portion of thedeveloping roller.

A process cartridge (20) according to the present invention includes: ahousing (21); and the photosensitive drum unit (30) according to claim11 which is held in the housing.

A process cartridge according to the present invention includes: ahousing; and the developing roller unit which is held in the housing.

An intermediate member (60, 160, 260) according to the present inventionis configured to be included in a bearing member (41, 141) which isarranged in an end portion of a columnar rotary body (35, 524) and towhich a shaft member (70) is attached, wherein the intermediate memberis configured to be arranged between a body (45, 145) of the bearingmember and the shaft member (70), the intermediate member including: aportion in which the shaft member is arranged so as to be swingable; anda guided portion which is guided by a portion of the body so that theintermediate member is swingable with respect to the body.

A body (45, 145) of a bearing member according to the present inventionis configured to be included in the bearing member (41, 141) configuredto be arranged in an end portion of a columnar rotary body (35, 524) andto attach a shaft member (70) to the bearing member, wherein the shaftmember is attached to the body via an intermediate member (60, 160,260), the body of the bearing member including: a cylindrical body (46);and a holding portion (50, 151) that is arranged inside the cylindricalbody and holds the intermediate member so as to be swingable, whereinthe holding portion includes an intermediate member guide (51, 52, 53,54, 151, 152) which guides the intermediate member so that theintermediate member rotates.

What is claimed is:
 1. A bearing member configured to be fitted in anend portion of a columnar rotary body, wherein a shaft member isattachable to the bearing member, the bearing member comprising: a bodythat includes a cylindrical body and a holding portion which is arrangedinside the cylindrical body; and an intermediate member that is held bythe holding portion of the body, wherein the holding portion includes anintermediate member guide which guides the intermediate member so thatthe intermediate member rotates, the intermediate member includes aportion in which the shaft member is arranged, and the intermediatemember includes a portion to receive a rotation force from the shaftmember.
 2. The bearing member according to claim 1, wherein theintermediate member guide is a guide groove into which an outerperipheral portion of the intermediate member is inserted, wherein theguide groove slides and guides the outer peripheral portion, and atleast a portion on a bottom surface of the guide groove is a curvedsurface.
 3. The bearing member according to claim 2, wherein the curvedsurface on the bottom surface of the guide groove comes into contactwith the outer peripheral portion of the intermediate member, therebyregulating a movement in a direction along an axis of the cylindricalbody of the intermediate member.
 4. The bearing member according toclaim 1, wherein a protruding guide member is disposed in theintermediate member, the intermediate member guide is a guide surface onwhich the guide member slides, and at least a portion of the guidesurface is a curved surface.
 5. The bearing member according to claim 4,wherein a guide member insertion groove is disposed in the holdingportion for causing the guide member to reach the guide surface.
 6. Thebearing member according to claim 5, wherein the guide member insertiongroove includes a snap-fit structure which is a portion narrower than anouter shape of the guide member.
 7. The bearing member according toclaim 6, wherein a groove into which a portion of a shaft member isinserted is disposed in the intermediate member, and the groove includesa snap-fit structure which is a portion narrower than an outer shape ofthe inserted portion of the shaft member.
 8. The bearing memberaccording to claim 7, wherein the snap-fit structure of the guide memberinsertion groove can be disengaged with a force weaker than a force forthe snap-fit structure of the groove disposed in the intermediatemember.
 9. The bearing member according to claim 7, wherein the snap-fitstructure of the guide member insertion groove needs to be disengagedwith a force stronger than a force for the snap-fit structure of thegroove disposed in the intermediate member.
 10. An end membercomprising: a shaft member; and the bearing member according to claim 1,wherein the shaft member includes: a rotary shaft; a rotation forcereceiving portion which is included on one end side of the rotary shaft,which can engage with a rotation force applying portion of an imageforming apparatus body, and which receives a rotation force from a driveshaft by maintaining an engaging posture thereof; a proximal end portionwhich is arranged on the other end side of the rotary shaft; and arotation force transmission projection which projects from the proximalend portion, wherein a groove with which the rotation force transmissionprojection engages is disposed in the intermediate member, and the shaftmember is assembled to the intermediate member by the rotation forcetransmission projection engaging with the groove.
 11. A photosensitivedrum unit, wherein the columnar rotary body is a photosensitive drum,and the photosensitive drum unit includes the photosensitive drum andthe end member according to claim 10 which is arranged in at least oneend portion of the photosensitive drum.
 12. A developing roller unit,wherein the columnar rotary body is a developing roller, and thedeveloping roller unit includes the developing roller and the end memberaccording to claim 10 which is arranged in at least one end portion ofthe developing roller.
 13. A process cartridge comprising: a housing;and the photosensitive drum unit according to claim 11 which is held inthe housing.
 14. A process cartridge comprising: a housing; and thedeveloping roller unit according to claim 12 which is held in thehousing.
 15. An intermediate member to be included in a bearing memberwhich is fitted in an end portion of a columnar rotary body and to whicha shaft member is attached, wherein the intermediate member isconfigured to be arranged between a body of the bearing member and theshaft member, the intermediate member comprising: a portion in which theshaft member is arranged so as to be swingable; a guided portion whichis guided by a portion of the body so that the intermediate member isswingable with respect to the body, and the intermediate member includesa portion to receive a rotation force from the shaft member.
 16. A bodyof a bearing member to be included in the bearing member configured tobe fitted in an end portion of a columnar rotary body and to attach ashaft member to the bearing member, wherein the shaft member is attachedto the body via an intermediate member, the body of the bearing membercomprising: a cylindrical body; and a holding portion that is arrangedinside the cylindrical body and holds the intermediate member so as tobe swingable, wherein the holding portion includes an intermediatemember guide which guides the intermediate member so that theintermediate member rotates, and wherein the intermediate memberincludes a portion to receive a rotation force from the shaft member.17. A bearing member configured to be fitted in an end portion of acolumnar rotary body, wherein a shaft member is attachable to thebearing member, the bearing member comprising: a body that includes acylindrical body and a holding portion which is arranged inside thecylindrical body; and an intermediate member that is held by the holdingportion of the body, wherein the holding portion includes anintermediate member guide which guides the intermediate member so thatthe intermediate member rotates, the intermediate member includes aportion in which the shaft member is arranged, and wherein the shaftmember includes a rotation force transmission pin and the intermediatemember holds the rotation force transmission pin.